Caring for obese people is eating up an ever-bigger slice of the U.S. health care spending pie, a new government report shows.

From 2001 to 2006, health care expenditures on obese adults rose from $167 billion to $303 billion, an 82 percent jump, according to an analysis by Marie N. Stagnitti, a senior survey statistician at the Agency for Healthcare Research and Quality in Rockville, Maryland.

Costs for overweight individuals rose 36 percent, from $202 billion to $275 billion, while spending on normal-weight people rose 25 percent, from $208 billion to $260 billion.

"Obviously we need to get this under control," Stagnitti told Reuters Health. "This is just another way to cut the data show that, especially for the obese population, we need to figure out what's going on there."

Obese people accounted for 28 percent of total health care spending in 2001, and 35 percent in 2006, the researcher found, while normal-weight people's share of these costs dropped from 35 percent to 30 percent.

During that time the number of obese adults in the US rose from 48 million to 59 million, while the number of normal weight adults actually fell slightly, from 79.6 million to 78.3 million.

The figures come from the Medical Expenditure Panel Survey, which samples US households on their health care spending, and account for the entire non-institutionalized civilian US population.

During the survey period, the proportion of overweight and obese people in the US population grew, which likely accounts for some of the increases in costs; in 2001, 23.6 percent of US adults were obese and 39 percent were normal-weight, compared to 27.2 percent and 36.1 percent, respectively, in 2006.

Stagnitti's analysis also showed that obese people accounted for the lion's share of the US population with at least a single chronic disease, like heart disease or diabetes. In 2001, 57.1 percent were obese, and in 2006 59.7 percent were obese.